MLE-World: Predicting Machine Learning Experiment Outcomes with a Learned World Model

Hugging Face Daily Papers Papers

Summary

MLE-World: a world model finetuned from Qwen3.5-4B that predicts ML experiment outcomes (error traces, logs, validation scores) without execution, enabling affordable test-time scaling for AI research agents. It matches real terminal outputs on 77.9% of held-out programs and boosts mean performance by up to 22.1% on MLE-bench Lite tasks.

AI research agents can propose, execute, and improve programs that solve machine learning tasks. However, executing each candidate program requires training and evaluating ML models, limiting how many candidates an agent can explore at each step. We introduce MLE-World, a world model finetuned from Qwen3.5-4B that predicts a program's terminal output (error traces, training logs, and validation scores) from its code and data description without executing it, together with a confidence score estimating the prediction's correctness. Because a prediction costs one inference call rather than a training run, MLE-World makes test time scaling (TTS) affordable for these agents. We build five TTS policies, guided by MLE-World, that compare several candidates per step by their predicted outputs: Sequential revision, Best-of-N, Pairwise judging, Fusion, and a UCB style rule that also adds an exploration bonus from this confidence score. Since predictions can be wrong, we run a candidate for real only when its confidence score is low. On 17 MLE-bench Lite tasks, MLE-World matches the real terminal output on 77.9% of held out programs, versus 41.1% for much larger prompted models. MLE-World guided TTS achieves up to 22.1% higher observed mean performance than the agent without a world model, with less real execution. Project webpage: https://mle-world.github.io/.
Original Article
View Cached Full Text

Cached at: 10/28/26, 05:25 AM

Paper page - MLE-World: Predicting Machine Learning Experiment Outcomes with a Learned World Model

Source: https://huggingface.co/papers/2610.37175

Abstract

A world model predicts machine learning program outcomes to enable affordable test-time scaling for AI research agents, improving performance with fewer real executions.

AI research agents can propose, execute, and improve programs that solve machine learning tasks. However, executing each candidate program requires training and evaluating ML models, limiting how many candidates an agent can explore at each step. We introduce MLE-World, aworld modelfinetuned fromQwen3.5-4Bthat predicts a program’s terminal output (error traces, training logs, and validation scores) from its code and data description without executing it, together with aconfidence scoreestimating the prediction’s correctness. Because a prediction costs one inference call rather than a training run, MLE-World makestest time scaling(TTS) affordable for these agents. We build five TTS policies, guided by MLE-World, that compare several candidates per step by their predicted outputs:Sequential revision,Best-of-N,Pairwise judging,Fusion, and aUCBstyle rule that also adds an exploration bonus from thisconfidence score. Since predictions can be wrong, we run a candidate for real only when itsconfidence scoreis low. On 17MLE-bench Litetasks, MLE-World matches the real terminal output on 77.9% of held out programs, versus 41.1% for much larger prompted models. MLE-World guided TTS achieves up to 22.1% higher observed mean performance than the agent without aworld model, with less real execution. Project webpage: https://mle-world.github.io/.

View arXiv pageView PDFProject pageAdd to collection

Get this paper in your agent:

hf papers read 2610\.37175

Don’t have the latest CLI?curl \-LsSf https://hf\.co/cli/install\.sh \| bash

Models citing this paper0

No model linking this paper

Cite arxiv.org/abs/2610.37175 in a model README.md to link it from this page.

Datasets citing this paper0

No dataset linking this paper

Cite arxiv.org/abs/2610.37175 in a dataset README.md to link it from this page.

Spaces citing this paper0

No Space linking this paper

Cite arxiv.org/abs/2610.37175 in a Space README.md to link it from this page.

Collections including this paper0

No Collection including this paper

Add this paper to acollectionto link it from this page.

Similar Articles

Language Models Learn to Improve Language Models

Hugging Face Daily Papers

LM2LM trains LLMs with reinforcement learning to propose effective language-model improvements, using a frozen research world model as a scalable reward signal with periodic real executions for reliability, enabling Qwen3.8-27B to outperform GPT-6-sol at 33% lower data-generation cost.

Q-Learning With World Models

arXiv cs.LG

This paper introduces QWM, a framework that integrates world models with Q-learning to enhance sample efficiency in reinforcement learning by using imagined trajectories for action selection without compromising training on real data. It demonstrates significant improvements over state-of-the-art methods on manipulation benchmarks.